qemu-kvm: Missing Release of Resource after Effective Lifetime
CVE-2022-26353 is a high-severity missing release of resource after effective lifetime vulnerability in qemu-kvm, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected qemu-kvm versions: Affected QEMU version: 6.2.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 2.74% chance of exploitation within 30 days, higher than 86% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of qemu-kvm you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on lists.nongnu.org for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Qemu-kvm | qemu-kvm | Affected QEMU version: 6.2.0 | Not stated |
| QEMU | Qemu | 6.2.0 | Not stated |
| Debian | Debian Linux | 11.0 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.5 | High | NVD |
| CVSS 2.0 | 5.0 | Medium | NVD |
Official description
A flaw was found in the virtio-net device of QEMU. This flaw was inadvertently introduced with the fix for CVE-2021-3748, which forgot to unmap the cached virtqueue elements on error, leading to memory leakage and other unexpected results. Affected QEMU version: 6.2.0.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Missing Release of Resource after Effective Lifetime
The product does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed.
How developers prevent this class of flaw
- Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, languages such as Java, Ruby, and Lisp perform automatic garbage collection that releases memory for objects that have been deallocated.
- It is good practice to be responsible for freeing all resources you allocate and to be consistent with how and where you free resources in a function. If you allocate resources that you intend to free upon completion of the function, you must be sure to free the resources at all exit points for that function including error conditions.
More Missing Release of Resource after Effective Lifetime vulnerabilities (CWE-772)
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Patches and release notes
- gitlab.com/qemu-project/qemu/-/commit/abe300d9d894f7138e1af7c8e9c88c04bfe98b37Third Party Advisory
Third-party and government advisories
- security.gentoo.org/glsa/202208-27Third Party Advisory
- security.netapp.com/advisory/ntap-20220425-0003/Third Party Advisory
- debian.org/security/2022/dsa-5133Third Party Advisory
Recent Missing Release of Resource after Effective Lifetime vulnerabilities
- 7.5 High severity
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